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Two series of polydentate N,O,S-ligands containing thiourea fragments attached to a p-cresol scaffold, unsymmetrical mono-acylated bis-amines and symmetrical bis-thioureas, are obtained by common experiments. It is observed that the reaction output is strongly dependent on both bis-amine and thiocarbamic chloride substituents. The products are characterized by 1D and 2D NMR spectra in solution and by single crystal XRD. A preliminary study on the coordination abilities of selected products is performed by ITC at around neutral media. [ABSTRACT FROM AUTHOR]

The present work focuses on the removal of dyes from polluted water, and, more precisely, the targets are crystal violet (CV) and methylene blue (MB). For this purpose, a series of Zr-modified catalysts based on microporous Engelhard Titanium Silicate 10 (ETS-10) were developed and synthesized. Aiming at improvement in the photodegradation efficiency and stability of ETS-10, Zr centers replacing part of Ti ones were introduced during the synthesis procedure. The obtained Na-K-ETS-10/xZr catalysts were characterized by X-ray powder diffraction (XRD), wavelength dispersive X-ray fluorescence (WDXRF), N2 physisorption and Fourier transform infrared spectroscopy (FTIR). The photocatalytic properties of Na-K-ETS-10/xZr- (x = 5, 10, 15 and 20 wt% Zr) catalysts were studied in terms of water purification from crystal violet and methylene blue. The Na-K-ETS-10/xZr wt% x = 6 catalyst appeared to be the most efficient in the photodegradation of CV and MB, removing nearly 100% of the dyes. Kinetic studies showed that the removal of CV and MB is a rapid process and one, which obeys the non-linear pseudo-second-order model. [ABSTRACT FROM AUTHOR]

In this study, three series of polydentate N,O-ligands possessing unsymmetrical urea fragments attached to a p-cresol scaffold are obtained, namely mono- and bi-substituted open-chain aromatics, synthesised using a common experiment, as well as fused aryloxazinones. Separate protocols for the preparation of each series are developed. It is found that in the case of open-chain compounds, the reaction output is strongly dependent on both bis-amine and carbamoyl chloride substituents, while oxazinones can be effectively obtained via a common protocol. The products are characterized via 1D and 2D NMR spectra in solution and using single-crystal XRD. A preliminary study on the coordination abilities of the products performed via ITC shows that there are no substantial interactions in the pH range of 5.0–8.5 in general. [ABSTRACT FROM AUTHOR]

The novel compound 2-(1H-imidazol-2-yl)-2,3-dihydro-1H-perimidine was obtained in very good yield via a known eco-friendly protocol. The product was isolated in pure form as a solvate by simple filtration from the crude mixture. Its structure was assigned by 1D and 2D NMR experiments and was confirmed by high resolution MS and single crystal XRD. The temperature of methanol release was determined by DSC and the energy of the process theoretically estimated. [ABSTRACT FROM AUTHOR]

A series of acylpyrazolones possessing a methylene bridged heterocyclic unit in the acyl fragment are synthesized and characterized in solution and the solid state. It is found that the products exist in the solid state as intramolecular or intermolecular zwitterions between the tautomeric pyrazolone hydroxyl group and the nitrogen atom of the acyl substituents. Aliphatic amine units with a variable number and type of heteroatoms and ring size are attached and the type of zwitterions formed are analysed by single crystal XRD. It is observed that the products coordinate spontaneously with cesium carbonate being used as a base. These complexes are also studied by XRD. [ABSTRACT FROM AUTHOR]

Here, we describe the synthesis, characterization, and biological activities of a series of 26 new styryl-2(3H)-benzothiazolone analogs of combretastatin-A4 (CA-4). The cytotoxic activities of these compounds were tested in several cell lines (EA.hy926, A549, BEAS-2B, MDA-MB-231, HT-29, MCF-7, and MCF-10A), and the relations between structure and cytotoxicity are discussed. From the series, compound (Z)-3-methyl-6-(3,4,5-trimethoxystyryl)-2(3H)-benzothiazolone (26Z) exhibits the most potent cytotoxic activity (IC50 0.13 ± 0.01 µM) against EA.hy926 cells. 26Z not only inhibits vasculogenesis but also disrupts pre-existing vasculature. 26Z is a microtubule-modulating agent and inhibits a spectrum of angiogenic events in EA.hy926 cells by interfering with endothelial cell invasion, migration, and proliferation. 26Z also shows anti-proliferative activity in CA-4 resistant cells with the following IC50 values: HT-29 (0.008 ± 0.001 µM), MDA-MB-231 (1.35 ± 0.42 µM), and MCF-7 (2.42 ± 0.48 µM). Cell-cycle phase-specific experiments show that 26Z treatment results in G2/M arrest and mitotic spindle multipolarity, suggesting that drug-induced centrosome amplification could promote cell death. Some 26Z-treated adherent cells undergo aberrant cytokinesis, resulting in aneuploidy that perhaps contributes to drug-induced cell death. These data indicate that spindle multipolarity induction by 26Z has an exciting chemotherapeutic potential that merits further investigation. [ABSTRACT FROM AUTHOR]